BRONKHORST EL-FLOW Select Series - Valve Safe State; Manual controls

Bronkhorst®
Instruction Manual EL-FLOW® Select9.17.099F 21
3.4 Valve Safe State
When a controlling instrument is not powered, the control valve automatically returns to its default state (also called Safe
State), which is closed for a 'normally closed' valve (n/c) and fully open for a 'normally open' valve (n/o). To protect the
system, certain events (such as communication errors) may cause the instrument to switch to Valve Safe State (see also LED
indications).
Check the serial number label or the technical specifications to see which valve type is used on your instrument (if
applicable).
3.5 Manual controls
On top of the housing, the instrument is equipped with two LED indicators and a multifunctional
switch, which can be used to monitor the instrument visually and start several functions manually.
3.5.1 LED indications
The LEDs on top of the instrument indicate the operational state. The meaning of some indications depends on the specific
fieldbus interface of the instrument (if installed).
•
(green) Mode: operation mode indication
•
(red) Error: error/warning messages
The tables below list the different LED indications:
•
Green
Pattern
Time
Indication
off
continuous
Power off or program not running
on
continuous
Normal operation mode
short flash
0.1 sec on,
2 sec off
No communication, valves are in safe/default state
blink
0.2 sec on,
0.2 sec off
Special function mode; the instrument is busy performing a special function (e.g.
auto-zero or self-test)
long flash
2 sec on,
0.1 sec off
Configuration mode; the 9-pin D-sub connector is set for RS232 communication
(ProPar) at 38400 Baud